T-square-clamping device.



PATENTED AUG. 25, 1903.

G. H. H. BMBTT. T-SQUARE GLAMPING DEVICE.

APPLICATION FILED APR. 28, 1902.

N0 MODEL.

wmvsssss ray: fl/ fmeff rron/v5) 25 my invention.

- U NITED STATES Patented August 25, 1903.

PATENT OFFICE.

GEORGE HENRY HAWKINS EMETT, OF NEW WESTMINSTER, CANADA, 'ASSIGNOR TO PIERRE'BARNES, OF SEATTLE, WASHINGTON.

T-SQUARE- CLAM PING DEVICE.

SPECIFICATTON forming part of Letters Patent No. 737,090, dated August 25, 1903.

: Application filed April 28, 1902.

! ing drawings.

This invention relates to drafting instruments, and particularly to clamps for T- squares.

The object of the invention is to provide a x holder or clamp of this class which will be simple, inexpensive; and easy of adjustment and which will securely hold a T-square to any set position transversely of the drawing board. This object is attained by the device or devices hereinafter fully described and which is illustrated in the accompanying drawings, in which-- Figure 1 is a plan view of a T-square se cured to a set position on a drawing-board by Fig. 2 is a front elevation thereof. Figs. 3 and 4 are respectively perspective views of the blade attachment A and clamp 0, shown in the other views.-

The blade attachment A consists of a plate '50 adapted to lie fiat upon the outer endof the T-square blade B and is provided with a tongue t, depressed below its under surface for hooking or engaging in the hole It, commonly made in the square-blade in proximity 3 5 to its end. The clamp O is formed of a plate 10, having a bend or flange fat right angles to the plate-body and provided with a threaded aperture 01, through which is passed a clamping-screw s, registering therewith. At

40 one end of the said screw'is a'milled head e,

integral with the screw, and loosely secured to the other end by riveting is a washer w. Holes g and g are provided, respectively, in

Serial No. 104,927. (No model.)

applied to T-squares of varying lengths usedupon a drawing-board by simply changing the wire. Also by putting a tension through the T-square blade upon the stock the latter bears firmly against the edge of the board and presents a right angle thereto. Further, it is capable of carrying a triangle or protractor the entire length of the blade and permits greater.

freedom of movement to the draftsman in the use of both hands to his work. He can, for instance, work on either side of a triangle, as the light or other circumstances may render desirable, and in plotting the Vernier of the protractor may be adjusted with one hand and the markings made coincidently with the other.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

The herein-described device, comprising a T-square-blade attachment having a projection therebeneath for engaging with the hole in the said blade end, a clamp formed of a plate having a bend therein and a screw passed through a threaded aperture thereof; and connection between the said attachment and the clamp, substantially as set forth. v In testimony whereof I affiir my:signature in presence of two witnesses.

GEORGE HENRY HAWKINS ElilET'lv Witnesses:

WM. GORDON, J. C. BRIDGMAN. 

